The radius of a cylinder is increased by a factor of 5. The height is not changed. 
What is the effect of the increase on the volume of the cylinder?
A)	The volume of the cylinder increases by a factor of 5.	 
B)	The volume of the cylinder increases by a factor of 25.	 
C)	The volume of the cylinder increases by a factor of 15.	
D)	The volume of the cylinder increases by a factor of 10.